OBJECTIVE - To study the implications of implementing the International Association of Diabetes in Pregnancy Study Group (IADPSG) recommendations for screening and diagnosis of gestational diabetes mellitus (GDM) in Israel and explore alternative methods for identifying women at risk for adverse pregnancy outcomes. RESEARCH DESIGN AND METHODS - We analyzed data of the Israeli Hyperglycemia and Adverse Pregnancy Outcomes study participants (N = 3,345). Adverse outcome rates were calculated and compared for women who were positive according to 1) IADPSG criteria, 2) IADPSG criteria with risk stratification, or 3) screening with BMI or fasting plasma glucose (FPG). RESULTS - Adopting IADPSG recommendations would increase GDM diagnosis by ∼50%. One-third of IADPSG-positive women were at low risk for adverse outcomes and could be managed less intensively. FPG ≥89 mg/dL or BMI ≥33.5 kg/m2 at 28-32 weeks of gestation detected proportions of adverse outcomes similar to IADPSG criteria. CONCLUSIONS - Implementing IADPSG recommendations will substantially increase GDM diagnosis. Risk stratification in IADPSG-positive women may reduce over-treatment. Screening with FPG or BMI may be a practical alternative.